The skyline of Helsinki is about to change, and the city’s planning department is almost giddy about it.

“You don’t often make Finland’s longest bridge in the center of its capital,” said Jari Tirkkonen, a project director for the city’s Economic and Planning Centre.

The bridge will connect the Helsinki peninsula to Kruunuvuorenranta, a new mixed-use development on former industrial land. Tirkkonen, whose duties include managing the development for the city, said the bridge is expected to accommodate bicycles, pedestrians and light rail -- but not cars.

A car-less bridge of this magnitude is hard to imagine in other parts of the world, especially the United States. Ville Lehmuskoski, Helsinki’s director of transportation and traffic planning, said he doesn’t know of another transit-only bridge of this scale anywhere in Europe. He’s hoping the new bridge will be unusual enough to draw tourists to the city.

And what a bridge it will be. A design competition, currently underway, has attracted entries from some of the top firms in the world. “These guys can do anything,” said Tirkkonen of the companies competing to design the bridge. “They can do miracles.” The original list of 50 entries has been whittled down to 10 finalists, and a winner will be announced in June.

The bridge design is a sensitive issue. Most of the buildings in the City Centre top out at five or six stories, so the profile of the new bridge will stand out. “This skyline has been fought for throughout history,” Tirkkonen said. In addition, the bridge is not far from Suomenlinna, an 18th century fortress that has been named a UNESCO World Heritage site. Tirkkonen said the terms of the competition “leave to the competitors to decide whether the bridge should be a contrasting element of its surroundings or just sort of melt in.”

The bridge furthers the city’s long-term plan to increase reliance on public transit, and to support dense, walkable residential development within the City Centre. Helsinki's current population is about the same as Washington, D.C.’s, but the city is growing all the time, said Pekka Sauri, Helsinki’s deputy mayor for public works and environmental affairs. “The more housing you provide, the more people want to move in. You never really catch up,” he said.

But expansion is difficult for a city surrounded by water, so planners looked within the city limits for development opportunities. Like many coastal cities, Helsinki had several industrial areas and commercial ports close to the financial district. Helsinki’s industrial land was not privately owned, so city planners had an unusual amount of power. About ten years ago, officials began canceling leases on city-owned industrial land along the water, according to Tirkkonen. The industrial ports moved to the edge of town in 2008, and freed up several large plots of brownfield land.

The Kruunuvuorenranta area, three kilometers from the City Centre on the island of Laajasalo, had been used as an oil port since the 1920s. Fifteen years from now, planners are hoping it will be a thriving community with housing, retail and office space. The city is already building infrastructure such as roads and utilities, and is making plans for an automated vacuum waste collection system. Developers are expected to begin building homes and commercial space within the next year.

Altogether, Kruunuvuorenranta and several similar developments currently in the works will increase the residential and commercial capacity of downtown Helsinki by fifty percent by the mid 2020’s, according to Lehmuskoski. He’s concerned about what development at this scale will do to the city’s transportation grid. “The road network will reach its limits,” he said. Expanding the city’s already robust public transit system is crucial. Today, an impressive 73 percent of the people who travel to the City Centre during the morning commute use public transit, a rate Lehmuskoski would like to maintain and even improve upon when the new developments are completed.

A lot is riding on the new bridge. Currently, the light rail network is confined to the City Centre, but the bridge would allow Lehmuskoski’s team to expand the network to the eastern part of the city, and significantly cut travel time during peak commute hours. Without the bridge, it would take residents of Kruunuvuorenranta 25 minutes to drive to the City Centre, and 33 minutes to make the trip via public transit. The light rail bridge would reduce the travel time to 19 minutes.

Sauri is hoping the new bridge will make the development more attractive both to existing Helsinki residents and to immigrants. “We already have some so-called white flight, where original inhabitants move out of the eastern part of the city and people with immigrant backgrounds grow out of proportion,” he said. “We try to keep it integrated and mixed.”

But the future of the bridge is uncertain. “We have not allocated the money for the bridge yet,” Sauri admitted. The most likely configuration, which would include light rail, cyclists and pedestrians, is projected to cost about 210 million euros, according to Tirkkonen. But the City Council has not fully committed to this option, and the idea of including cars on the bridge is still under discussion. Tirkkonen said a car bridge would be almost twice the size of the proposed transit bridge, and the price tag would be almost twice as large as well, which would strain the city’s budget in these lean economic times.

Planners are confident enough that they’re going ahead with the assumption that the bridge will not include car traffic. Tirkkonen said the main road through the development has already been built with light rail in mind. It’s much wider than a normal road, because there will be space for trams to run in either direction in the center island, with automobile traffic flanking the tracks. If trams aren’t routed to the development, the extra expense of the wider road will have been wasted. If there are cars on the bridge, traffic problems would be created at either end of the bridge.

Helsinki’s large-scale brownfield redevelopment is arguably just as innovative as the transit bridge, but city leaders are most excited about the bridge. Tirkkonen recalls discussions in City Council, where politicians from multiple political parties were talking about the bridge. “Let's make it a landmark,” they said. “Like the Golden Gate of Helsinki.”